[Bug build/31399] Build fails on macOS: error: cannot cast 'tui_win_info *' to 'tui_cmd_window *' via virtual base 'tui_win_info'

["cvs-commit at gcc dot gnu.org" <sourceware-bugzilla@sourceware.org>]

https://sourceware.org/bugzilla/show_bug.cgi?id=31399

--- Comment #4 from Sourceware Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Andrew Burgess <aburgess@sourceware.org>:

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=7d18eb9983b00455fd2f3100d4de2772c3f656ad

commit 7d18eb9983b00455fd2f3100d4de2772c3f656ad
Author: Andrew Burgess <aburgess@redhat.com>
Date:   Wed Mar 6 17:28:48 2024 +0000

    gdb: use static_cast in gdb::checked_static_cast

    This commit:

      commit 6fe4779ac4b1874c995345e3eabd89cb1a05fbdf
      Date:   Sat Feb 24 11:00:20 2024 +0100

          [gdb/build] Fix static cast of virtual base

    addressed an issue where GDB would not compile in production mode due
    to a use of gdb::checked_static_cast.  The problem was that we were
    asking GDB to cast from a virtual base class to a sub-class, this
    works fine when using dynamic_cast, but does not work with
    static_cast.

    The gdb::checked_static_cast actually uses dynamic_cast under the hood
    in development mode in order to ensure that the cast is valid, while
    in a production build we use static_cast as this is more efficient.

    What this meant however, was that when gdb::checked_static_cast was
    used to cast from a virtual base class, the dynamic_cast of a
    non-production build worked fine, while the production build's
    static_cast caused a build failure.

    However, the gdb::checked_static_cast function already contains some
    static_assert calls that are intended to catch any issues with invalid
    type casting, the goal of these asserts was to prevent issues like
    this: the build only failing in production mode.  Clearly the current
    asserts are not enough.

    I don't think there is a std::is_virtual_base type trait check, so
    what I propose instead is that in non-production mode we also make use
    of static_cast.  This will ensure that any errors that crop up in
    production mode should also be revealed in non-production mode, and
    should catch issues like this in the future.

    There should be no user visible changes after this commit.

    Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=31399

    Co-Authored-By: Simon Marchi <simon.marchi@polymtl.ca>

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